JP2003297901A - Substrate treating system and treating method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the conveying method of a semiconductor wafer for restraining the generation of a natural oxide film, a water mark or the like in cleaning the semiconductor wafer. <P>SOLUTION: The semiconductor wafer is conveyed by a method wherein first and second treating chambers 110, 120 and a drying unit 130 are arranged vertically in a housing 100 and the wafer is conveyed between the treating chambers and the drying unit by a first non-contact retaining type conveyor robot 140 while the wafer is conveyed between the housing 100 and a wafer cassette 160 by a second non-contact retaining type conveyor robot 150 and nitrogen gas is supplied from a gas supplying port 170 into the housing 100. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate processing system and a processing method thereof, and more particularly to a processing system and a processing method for cleaning semiconductor wafers.

[0002]

2. Description of the Related Art Cleaning technology for semiconductor wafers has become more and more important with the miniaturization of LSIs. What is important in the semiconductor wafer cleaning process is to remove impurities such as particles and heavy metals up to the previous process, remove the chemicals used in the cleaning process, and generate defects such as particles and watermarks in the cleaning process. Is to suppress. The cleaning of semiconductor wafers is generally wet cleaning, and cleaning is performed using chemicals such as acids, alkalis and organic solvents.

A typical cleaning process includes a first step of removing particles and the like from a silicon wafer, and a second step of removing an unnecessary natural oxide film on the silicon surface.
It comprises a third step of removing heavy metals adhering to the silicon wafer, each of which is subjected to the desired chemical cleaning. In the first step, ammonia water, hydrogen peroxide water,
An alkaline mixed solution consisting of ultrapure water (hereinafter referred to as SC-1) is used, hydrofluoric acid diluted with ultrapure water (hereinafter referred to as diluted hydrofluoric acid) is used in the second step, and the third step is used. In general, an acidic mixed solution (hereinafter referred to as SC-2) composed of hydrochloric acid, hydrogen peroxide solution, and ultrapure water is used. Further, a rinse process using ultrapure water is performed between these steps. And finally, complete drying takes place in the drying unit.

[0004]

The conventional wet station type requires an explosion-proof structure because the wafer moving distance between cleaning processes for cleaning is long and IPA drying is used. Furthermore, since the natural replacement of IPA drying is awaited, the throughput of wafer cleaning is suppressed. For these reasons, watermarks and natural oxide films are always generated. Even if it is attempted to maintain the inside of the apparatus in a nitrogen atmosphere completely, the apparatus becomes large in size and very expensive, which is impractical.

On the other hand, in the spin single wafer cleaning machine type, one of the surfaces of the silicon substrate must be directly contacted over a wide area by a method such as suction when the wafer is transferred, and therefore the wafer is transferred, for example, in the next step. However, when extremely high cleanliness such as film formation is required, it is considered unsuitable because of concern about contamination. Further, although the wafer can be moved in a short time until the drying, the spin drying is mainly performed, so that the formation of the watermark and the natural oxide film is inevitable. Although it is possible to use IPA, forcible replacement of IPA may cause unreasonableness or insufficiency in the process, and an explosion-proof structure needs to be provided as an apparatus, resulting in high cost.

FIG. 13 is a diagram showing a step of forming a wiring layer on a silicon substrate when the conventional spin single wafer cleaning machine type is used. FIG. 1A shows a state in which an etching process is performed to form a contact hole (or a via hole) 3 in an insulating film 2 (SiO 2 or the like) on a silicon substrate 1. After the etching process, the process unnecessary substance 4 is attached to the inner wall of the contact hole 3 of the insulating film 2 at the time of the etching in the previous step, and the natural oxide film 5 is formed on the exposed surface of the silicon substrate. Therefore, the Si wafer is washed to remove the process unnecessary substances 4 and the natural oxide film 5.

FIG. 1B shows a state after the cleaning treatment with the chemical agent. In this state, high cleanliness is temporarily achieved by the chemical treatment, but if the drying is not sufficiently taken into consideration, residual moisture 6 will be generated due to unevenness in drying, which will later become a watermark (stain). In particular, the higher the aspect ratio of the contact hole 3, the more likely it is to occur, for example, when it exceeds 3.

After the drying step, if the Si wafer is easily exposed to the atmosphere or the atmosphere is not controlled after the chemical treatment, the natural oxide film 5 is regenerated as shown in FIG. I will end up. Further, the remaining water content becomes the watermark 7. Most of these are thought to be caused by atmospheric oxygen.

When the next wiring layer is formed from this state, as shown in FIG. 3D, the silicon surface and the wiring layer 8 are formed.
Since the native oxide film 5 and the watermark 7 remain at the interface with the wiring layer 8, good electrical connection of the wiring layer 8 cannot be performed. For this reason, the electrical reliability of the semiconductor device is deteriorated, and in some cases, it may cause failure or failure. Such a problem is not limited to the film forming process of the wiring layer shown in FIG. 13, and may similarly occur in the cleaning process performed in other manufacturing processes.

Therefore, the present invention solves the above-mentioned conventional problems, prevents the formation of a natural oxide film or a watermark during cleaning of a semiconductor wafer, and can manufacture a highly reliable semiconductor device. And a processing method. A further object of the present invention is to provide a semiconductor wafer processing system and method in which a plurality of cleaning processing chambers are vertically arranged to realize space saving and cost reduction. It is a further object of the present invention to provide an improved substrate processing system and method that isolates the substrate being processed from the atmosphere and suppresses the generation of particulates, cross contamination, etc. during substrate processing.

[0011]

In order to solve the above problems, a substrate processing system according to the present invention includes a first processing chamber for processing a substrate and a second processing chamber for processing the substrate between the first and second processing chambers. And a holding means for holding the substrate in a substantially non-contact state under an inert gas atmosphere.

[0012] Preferably, the substrate processing system has a housing including at least first and second processing chambers and a transfer means, and the first and second processing chambers are arranged in a vertical structure in the housing. Then, the inert gas is supplied into the housing. It is preferable that the housing provides a space that is shielded from the atmosphere (substantially closed space), and the inert gas is supplied from the top of the housing.

The substrate in the above system is preferably a semiconductor wafer, the first and second processing chambers are chambers for cleaning the semiconductor wafer, and each chamber is placed in an inert gas atmosphere. The inert gas used in the system is preferably nitrogen gas. However, in addition to semiconductor wafers, it can be applied to substrates such as glass substrates for liquid crystal displays and glass substrates for plasma displays.

Preferably, the semiconductor wafer is held and transported in a substantially non-contact state by utilizing the Bernoulli effect. At least one main surface or the opposing surface of the semiconductor wafer is atmosphere-controlled with nitrogen gas. Therefore, in the process from cleaning to drying of the semiconductor wafer, the semiconductor wafer is substantially in an inert gas atmosphere and is not exposed to the atmosphere.

The semiconductor wafer processing system of the present invention comprises:
At least a first processing chamber, a second processing chamber, and a drying chamber are vertically arranged in a housing, and a semiconductor wafer is transferred between the first processing chamber, the second processing chamber, and the drying chamber. The first wafer transfer means holds the semiconductor wafer in a substantially non-contact state under an inert gas atmosphere.

Preferably, the first processing chamber, the second processing chamber, and the
And a drying chamber is disposed and a first
An inert gas is caused to flow from the processing chamber of 1 to the second processing chamber. Furthermore, the semiconductor wafer processing system is
A wafer accommodating portion for accommodating a plurality of semiconductor wafers, and a second conveyer semiconductor wafer between the wafer accommodating portion and the first processing chamber in an inert gas atmosphere and in a non-contact state.
Wafer transfer means. Since the semiconductor wafer accommodated in the wafer accommodating portion has not been cleaned, it is contaminated by the chemicals and particles in the previous process.
By using the second transfer means, the contamination in the wafer accommodation section is isolated from the housing.

Preferably, the first and second processing chambers are cleaning spinners for cleaning the semiconductor wafer with a chemical, and the first processing chamber performs SC-1 cleaning and the second processing chamber. Then, the native oxide film on the semiconductor wafer is removed using dilute hydrofluoric acid. Furthermore, if desired, a third processing chamber may be provided within the housing. In this case, the third processing chamber is, for example, SC-
2. Wash with 2.

The substrate processing method of the present invention is a substrate processing system in which a housing is provided with first and second processing chambers and a drying chamber, and an inert gas is supplied into the housing. A step of performing a cleaning process on the substrate, a step of controlling the surface of the substrate substantially in an inert gas atmosphere to transfer the substrate from the first chamber to the second chamber, and a process of cleaning the substrate in the second chamber. Transporting the substrate from the second chamber to the drying chamber by substantially controlling the atmosphere of the substrate with an inert gas atmosphere.

Preferably, the first and second chambers and the drying chamber are arranged vertically, and the substrate is a semiconductor wafer. The inert gas supplied into the housing and the inert gas controlling the atmosphere of the semiconductor wafer are preferably nitrogen gas. In addition, the semiconductor wafer is held in a substantially non-contact state, which is held using the Bernoulli effect.

According to the present invention, the inert gas (nitrogen gas) atmosphere can be realized in the housing at low cost by making the substrate processing system into a small chamber. Since the substrate is supported by the Bernoulli chuck using an inert gas in a non-contact state, the air in the atmosphere is not attracted to the substrate. Particularly in the case of semiconductor wafers, the strong nitrogen blowing effect of the Bernoulli chuck can assist the drying effect in the hole-shaped pattern. Also, by making the drying in the drying chamber dry under vacuum,
By using a vacuum pump and near-infrared light in combination, the drying of the semiconductor wafer can be further shortened, and further, the safety can be improved because no chemical substance such as IPA is used. As described above, the cleaning apparatus or system can be realized at a low cost and with high throughput, and further, it is possible to realize a wafer transfer / drying technique that does not generate a watermark or a natural oxide film after the cleaning process. As a result, it is possible to suppress the deterioration of the electrical characteristics of the semiconductor device and realize the production of a highly reliable semiconductor device.

[0021]

1 is a block diagram showing the concept of a semiconductor wafer cleaning processing system according to an embodiment of the present invention. In the figure, the cleaning processing system includes a first processing chamber 110, a second processing chamber 120, and a drying unit 130 in a small housing 100 that provides a substantially enclosed space. First and second processing chamber 11
0 and 120 and the drying unit 130 are vertically arranged in a multistage structure, and the semiconductor wafer is transferred between these chambers and units by the first transfer robot 140. The wafer cassette 160 accommodates a semiconductor wafer to be cleaned and a cleaned semiconductor wafer, and the inside thereof can be purged with nitrogen gas. The transfer of the wafer from the wafer cassette 160 to the first processing chamber 110 and the transfer of the wafer from the drying unit 130 to the wafer cassette 160 are performed by the second transfer robot 150. A gas supply port 170 for supplying nitrogen gas into the housing is provided at the top of the housing 100.

The first processing chamber 110 is a chamber for cleaning SC-1 which removes particles and the like from the semiconductor wafer, and the second processing chamber 120 removes unnecessary natural oxide film from the surface of the semiconductor wafer. This is a chamber for cleaning diluted hydrofluoric acid. The insides of the first and second chambers 110 and 120 are placed under a nitrogen atmosphere. The drying unit 130 is for finally drying the semiconductor wafer cleaned in the second processing chamber 120, and is composed of a vacuum heating device. As will be described later, the first and second transfer robots 140 and 150 have a function of holding a semiconductor wafer in a non-contact state and controlling the semiconductor wafer in an inert gas atmosphere.

The semiconductor wafers stored in the wafer cassette 160 are transferred to the first processing chamber 110 one by one by the second transfer robot 150. The semiconductor wafer is cleaned in the first processing chamber 110, and the process waste generated by the etching process of the previous step is removed. Next, the semiconductor wafer is transferred by the first transfer robot 140 to the second processing chamber 120 in a non-contact state and under nitrogen atmosphere control, where the unnecessary natural oxide film is removed using dilute hydrofluoric acid. Be seen. Next, the semiconductor wafer is supplied to the drying unit 130 and dried under nitrogen gas control in a non-contact state by the first transfer robot 140. The dried semiconductor wafer is transferred to the wafer cassette 160 by the second transfer robot 150 in a non-contact state and under nitrogen atmosphere control. Wafer cassette 16
After a predetermined number of wafers are accommodated in 0, the inside is purged with nitrogen gas.

The semiconductor wafer cleaning system of this embodiment is characterized in that the semiconductor wafer is held in a non-contact state to suppress the generation of particles and the like, and the semiconductor wafer is substantially exposed to the atmosphere without nitrogen. Put in a gas atmosphere. In other words, until the semiconductor wafer is taken out from the wafer cassette 160 and returned to the wafer cassette 160 again, the semiconductor wafer is completely controlled in a nitrogen gas atmosphere and held and conveyed in a non-contact state.

FIG. 2 is a diagram showing a step of forming a wiring layer on a silicon substrate by the semiconductor wafer cleaning processing system shown in FIG. In FIG. 3A, an insulating film 202 made of silicon oxide or the like is applied on a silicon substrate 201, and a contact 203 for making an electrical connection with the substrate.
Are formed by an etching process. At this time,
The process unnecessary material 20 is formed on the inner wall of the contact hole 203.
4 is attached, and a natural oxide film 205 is formed on the exposed surface of the silicon substrate. The etched semiconductor wafer is cleaned in the first chamber 110 and the second chamber 120, and as shown in FIG. 7B, the process unnecessary substances 204 and the natural oxide film 205 are removed cleanly. In this cleaning, the surface of the semiconductor wafer can be kept highly clean. The reason is that, at the time of wafer transfer, the transfer robot 140 controls the nitrogen gas atmosphere of the semiconductor wafer, and the nitrogen blow 206 is used in the housing 100.
This is because the semiconductor wafer is not substantially exposed to the atmosphere until being transferred to the drying unit 130.

Even after the wafer is dried in the drying unit 130, since the semiconductor wafer is transferred by the second transfer means 150 in the nitrogen gas atmosphere, the semiconductor wafer is not exposed to the presence of oxygen mainly in the atmosphere. ), A natural oxide film is not regenerated on the exposed surface of the silicon substrate 201 and a watermark is hardly generated. As shown in FIG. 6D, in the film formation process of the wiring layer 207, the silicon substrate 201 and the wiring layer 207, which are the most important, are surely connected, and a highly reliable product can be obtained. In addition to forming the wiring layer shown in FIG. 2, for example, in the case of forming the wiring layer after forming the via hole in the multilayer wiring structure, it is possible to suppress the generation of watermarks in the via hole, or to form the underlying polysilicon layer or the silicon substrate. Needless to say, it is possible to prevent regeneration of the natural oxide film on the surface and effectively prevent generation of watermarks and natural oxide films in various cleaning steps other than the above.

Next, a specific configuration of the semiconductor wafer cleaning processing system of this embodiment will be described. FIG. 3 is a plan view of the semiconductor wafer cleaning processing system, and FIG.
1 shows a schematic configuration by an X-ray section. In the semiconductor wafer cleaning processing system 300, a first cleaning processing chamber 320, a second cleaning processing chamber 330, and a drying chamber 340 are vertically arranged in a housing 310 having a substantially closed space so as to have a multi-stage structure. Housing 310
A hepa filter 350 for supplying a constant flow rate of nitrogen gas during the treatment is provided on the upper part of, and the nitrogen gas flows like a shower from the upper side to the lower side in the housing during the treatment. A first transfer robot 360 and a second transfer robot 370 are arranged on both sides of the processing chambers 320, 330, and 340, respectively. First transfer robot 3
The second transfer robot 370 transfers a semiconductor wafer between the processing chambers 320, 330, and 340.
Carries a semiconductor wafer between the wafer cassette 380 and each processing chamber. By using the first and second transfer robots 360 and 370 in this way, the housing 3
The interior of 10 can be substantially isolated from the external contaminant environment.

A pair of gate valves 321, 321 are provided on the surfaces of the processing chambers 320, 330, 340 facing each other.
331 and 341 are provided, and the semiconductor wafer can be taken in and out by opening and closing the gate valves. The opening / closing operation of the gate valves 321, 331, 341 is performed by the transfer robots 360, 37 under the control of a controller (not shown).
It is performed in synchronization with the movement of 0. The gate valve 32
1, 331, 341 are the other second transfer robots 36.
0 can be arranged on any of the four surfaces in the housing 310, depending on the device configuration. In addition, depending on the arrangement of the transfer robots 360 and 370, the gate valves do not necessarily have to be opposed to each other, and depending on the control of the control unit, the wafer can be taken in and out using only one gate on one side.

FIG. 5 shows a cross section of the wafer cassette. The pressure of the cassette may be set higher than that of the outside so that the particles do not adhere to the inside of the cassette 380.
Alternatively, a supply port 381 for purging nitrogen gas may be provided so as to keep the inside of the cassette in a nitrogen gas atmosphere.

FIG. 6 is a sectional view showing the structure of the first cleaning processing chamber. The second cleaning processing chamber also has basically the same configuration. As shown in the figure, the first cleaning processing chamber 320 has a housing 322 that provides the interior of a substantially closed space, and an opening 323 for loading and unloading a wafer is formed in the opposite surface of the housing 322.
Is formed. The opening 323 is the gate valve 3 during processing.
It is closed by 21. A cleaning spinner 324 is provided inside the housing 322. The cleaning spinner 324 includes a holding table 325 that holds the semiconductor wafer 400 in a non-contact state, a rotary drive unit 326 that rotates the holding table, and SC-1, SC-2, and dilute hydrofluoric acid for the wafer. A nozzle 328 for supplying a chemical treatment liquid 327 such as a chemical or ultrapure water.
A blowout port 329 for blowing out nitrogen gas is formed in the center of the holding table 325, and the blowout port 329 is connected to a nitrogen gas supply unit 329a for starting gas supply during processing. A certain amount of nitrogen gas is blown out from the air outlet 329, and the nitrogen gas is jetted toward one main surface of the semiconductor wafer 400 at a pressure of about 3.5 Kg per square centimeter, which causes a kind of Bernoulli effect. Are held on the holding table 325 in a substantially non-contact state. Several wafer fixing pins 325a are projected on the outer periphery of the holding table 325 at substantially equal intervals, and the position of the semiconductor wafer 400 in the radial direction is regulated by this. Also, depending on the arrangement of the transfer robot 360,
By installing the gate valve only in one direction, it is possible to carry the wafer in and out of each cleaning processing chamber from that direction.

FIG. 7 is a diagram showing the structure of the first transfer robot 360. The transfer robot 360 moves the semiconductor wafer 4 between the processing chambers 320, 330 and 340.
00 is conveyed one by one, and for that purpose,
The second robot arms 361a and 361b and the first and second holding surfaces 36 for holding the wafer in a non-contact state.
First and second non-contact holding portions 36 having 2a and 362b
3a and 363b. The first and second non-contact holders 363a and 363b are connected to the first and second robot arms 361a and 361b, respectively, and can be swung by the first and second drive units 367a and 367b. The first and second drive units 367a and 367b are supported on the support unit 364, and are capable of vertical movement and pivotal movement according to a command from a control unit (not shown). Holding surfaces 362a and 362a of the first and second non-contact holding portions 363a and 363b.
The reference numeral 62b is provided with a blowout port for nitrogen gas (see 803 in FIG. 9), and the first and second holding surfaces 362a and 362 are provided.
When 2b is positioned at a predetermined interval with respect to one main surface of the semiconductor wafer, nitrogen gas is blown from the holding surfaces 362a and 362b so that the semiconductor wafer can be held in a substantially non-contact state by utilizing the Bernoulli effect. ing.

FIG. 10 is a diagram showing the configuration of the second transfer robot 370. The second transfer robot 370 transfers the wafer between the wafer cassette 380 and the processing chamber inside the housing.
71 and a non-contact holding portion 373. The robot arm 371 is supported on the support part 374 and has a first arm part 375 capable of vertical movement and a rotational motion and second arm parts 376a and 376b performing bending and extension movements. The non-contact holding part 373 is connected to the second arm parts 376a and 376b, and the first and second arm parts 375 and 376 are connected.
It is possible to move in the horizontal direction by the movement of a and 376b. The non-contact holding portion 373 includes first and second non-contact holding portions 373a and 373b of the same type, and the non-contact holding portions 373a and 373b are respectively the first and second holding surfaces 3.
72a, 372b, each holding surface 372a, 372b
Is equipped with an outlet for blowing out nitrogen gas. The semiconductor wafer can be held in a non-contact state by utilizing the Bernoulli effect by the gas blown from the holding surfaces 372a and 372b. Further, one main surface of the semiconductor wafer can be placed in a nitrogen gas atmosphere, and the semiconductor wafer can be isolated from the outside air.

In this embodiment, when the contaminated semiconductor wafer 400 in the wafer cassette 380 is transferred to the first cleaning processing chamber 320, the first non-contact holding unit 3 is used.
63a and 373a are used, and on the other hand, when returning the cleaned and dried semiconductor wafer 400 to the wafer cassette 380, the second non-contact holding portions 363b and 373b are used. In this way, by assigning the first non-contact holding part 373a to holding and carrying the contaminated semiconductor wafer and assigning the second non-contact holding part 373b to holding and carrying the uncontaminated semiconductor wafer, Not a little, cross contamination of semiconductor wafers can be prevented.

8 and 9 show the first transfer robot 36.
It is a front view of the non-contact holding part 363a (363b) of 0, and its principal part sectional drawing. Although the configuration of the first non-contact holding portion is shown here, the second non-contact holding portion also has a common configuration.
The first non-contact holding portion 363a has a holding surface 362a, a mechanism 801 for restricting horizontal movement of the semiconductor wafer 400 held in a non-contact state, and a gas outlet 8.
Gas path 802 connected to H.03 and optical sensor 80
Including 4. The mechanism 801 for restricting the movement is arranged in a rectangular parallelepiped space formed by the holding surface 362a and a cover fixed to the holding surface 362a.

The holding surface 362a is formed on the semiconductor wafer 400.
It has a circular shape having a size equal to or close to that, and has a blowout port 803 for blowing out nitrogen gas at the center thereof and an optical sensor 804 at a position slightly apart from this.
The gas outlet 803 is connected to the gas path 802,
The gas path 802 is connected to a gas supply unit (not shown),
A constant amount of nitrogen gas is supplied when holding a semiconductor wafer. Nitrogen gas is the gas outlet 8
The semiconductor wafer 400 is blown from 03 onto the semiconductor wafer 400, and the semiconductor wafer 400 is sucked and floated. Semiconductor wafer 40
A mechanism 801 for restricting the horizontal movement of 0 is, for example, a pair of claws 805 such as Teflon (registered trademark) and a microcylinder 80 for opening and closing the pair of claws 805.
6, a guide 807 for holding the claw 805. The pair of claws 805 are arranged on both left and right sides of the holding surface 362a, and their bases are fixed to the shaft of the guide 807.
The inner wall of the claw 805 has a curvature surface that is substantially equal to the curvature of the semiconductor wafer 400, and the tip of the claw 805 projects inward (in the radial direction of the semiconductor wafer).
It also serves as a fall prevention mechanism for the semiconductor wafer 400. The guide 807 connected to the claw 805 is the microcylinder 8
It is possible to move in the horizontal direction X (horizontal direction toward the drawing) by 06. When the micro cylinder 806 is driven by a command from the control unit, each claw 805 is guided by the guide 807.
The position of the claw 805 is adjusted so that the levitated semiconductor wafer 400 is in a horizontal position within a certain range, and is preferably slightly smaller than the outer diameter of the semiconductor wafer 400. The semiconductor wafer 400 located outside and in a non-contact state is guided. On this occasion,
The outer diameter of the semiconductor wafer 400 is not always in contact with the inner wall of the claw 805, but its outer diameter is sometimes in contact with the inner wall of the claw 805 in order to correct its position or trajectory. Further, the claw 805 is moved further inward so that the claw 805
It is also possible to abut on the outer diameter of the semiconductor wafer 400 and clamp it completely. The optical sensor 804 detects the presence or absence of the semiconductor wafer 400 and supplies the detection result to a control unit (not shown).

When nitrogen gas is blown from the holding surface 362a of the non-contact holding portion 363a and the semiconductor wafer 400 is sucked up from the upper surface by the Bernoulli effect and floated,
There is a certain gap between the holding surface 362a and one main surface of the semiconductor wafer can be placed in a nitrogen gas atmosphere, and the wafer is completely shielded from the atmosphere (oxygen). When the semiconductor wafer is held in a non-contact state, the claw has a fall prevention mechanism, and for example, the fall of the semiconductor wafer 400 can be avoided even if the Bernoulli effect is weakened due to a sudden accident during transportation. .

11 and 12 are a front view and a side view of the non-contact holding section 373a (372b) of the second transfer robot 370. Here, the first non-contact holding portion 373a
However, the second non-contact holding portion 373b also has a common configuration. The contact holder 373a is a holder 9 having a short shape.
00, the length of the holder 900 in the longitudinal direction is larger than the diameter of the semiconductor wafer 400, and the width in the direction perpendicular to the longitudinal direction is smaller than the diameter. The thickness of the holder 900 is
It should be such that it can be inserted between the wafers accommodated in the wafer cassette 380, and 3 mm or less is the best. On the holding surface 372a, a blowout port 901 for blowing out nitrogen gas, a guide 902 such as Teflon for restricting the horizontal movement of the semiconductor wafer 400 held in a non-contact manner, and a clamping mechanism for clamping the semiconductor wafer. A light sensor 904 and an optical sensor 909 are provided.

The gas outlet 901 is connected to a gas passage 905 passing through the inside of the holder 900, and the gas passage 905 is connected to the gas passage 905.
Is connected to a gas supply unit (not shown) and supplies a fixed amount of nitrogen gas when holding the semiconductor wafer. The gas is blown from the gas blowout port 901 to the semiconductor wafer to float the semiconductor wafer. The clamp mechanism 904 includes a guide 906 such as Teflon,
It has a bracket 907 that holds the guide 906 and a microcylinder 908 that moves the bracket 907. When the microcylinder is driven by a command from the control unit, the guide 906 contacts the semiconductor wafer 400 via the bracket 907, Can be clamped. The optical sensor 909 detects the presence / absence of a semiconductor wafer and supplies the detection result to a controller (not shown).

Next, the operation of the wafer cleaning process according to this embodiment will be described. For example, an etched semiconductor wafer is stored in the wafer cassette 380. The first non-contact holding unit 3 of the second transfer robot 370
73a takes out the wafers one by one from the wafer cassette 380 and conveys the wafers.
The non-contact holding unit 363 a receives the wafer and transfers the wafer to the processing chamber 320. The contaminated wafer in the wafer cassette 380 is held in a substantially non-contact state and is transferred under a controlled nitrogen atmosphere. The semiconductor wafer 400 is transferred from the first non-contact holding unit 363 a to the holding table 325 of the cleaning spinner 324 via the gate valve 321 of the first cleaning processing chamber 320. Positioning the first non-contact holding portion 363a on the holding table 325,
Next, by blowing out nitrogen gas from the blowing port 329 of the holding table 325 and stopping the blowing of nitrogen gas from the non-contact holding portion 363a, the upper surface of the semiconductor wafer loses the suction force by the non-contact holding portion 363a, and at the same time. The lower surface is attracted to the holding table 325, and the transfer is completed. The semiconductor wafer 400 is held in a non-contact state on the holding table 325, rotated by the rotation driving unit 326, and the nozzle 32
A chemical is dropped from No. 8, and SC-1 class cleaning is performed, for example. Next, pure water is dropped from the nozzle 328 onto the wafer to perform a rinse for removing chemicals, and spin drying is performed. At this time, the inside of the processing chamber, that is, the housing 322 is under a nitrogen gas atmosphere, and the semiconductor wafer is not exposed to the atmosphere. The wafer transfer between the second transfer robot 370 and the first transfer robot 360 may be performed directly between the robots by appropriately controlling the driving of the non-contact holding unit, or a transfer table dedicated to transfer is provided. Alternatively, the wafers may be handed over by using them together.

The wafer cleaned in the first cleaning processing chamber 320 is then transferred to the second processing chamber 330 by the first transfer robot 360. The second non-contact holder 363b of the first transfer robot 360 is positioned on the holder 325 of the cleaning spinner via the gate valve 321 of the first cleaning processing chamber 320. Here, the gas outlet 90 of the second non-contact holding portion 363b.
1. Nitrogen gas is blown out from the holding base 325 in this state.
The gas blowing from the outlet 329 of No. As a result, the lower surface of the semiconductor wafer loses the suction force from the holding table 325, while the upper surface of the wafer is attracted to the second non-contact holding section 363b and transferred from the holding table 325 to the second non-contact holding section 363b. Loading is completed. The wafer is similarly transferred from the first cleaning processing chamber 320 to the second cleaning processing chamber 330, but the semiconductor wafer is controlled in a nitrogen gas atmosphere by the nitrogen gas blown from the second non-contact holding unit 363b, and Nitrogen gas is supplied into the processing system through the filter 350, and the semiconductor wafer is in a nitrogen gas atmosphere and completely shielded from the atmosphere <oxygen>.

The wafer transferred to the second cleaning processing chamber 330 is held in a non-contact state by the holding table 325, and a chemical such as HF is dropped from the nozzle 328 to remove an unnecessary natural oxide film. Be seen. At this time, since the wafer is under a nitrogen gas atmosphere, the rate of formation of an oxide film on the exposed surface of the silicon substrate is extremely low.
After the HF and other chemicals are treated as described above, the semiconductor wafer that has been rinsed and spin-dried is transferred to the drying chamber 340 by the second transfer robot 373b. The drying chamber 340 includes a vacuum heating device and heats the wafer in a vacuum state to dry the wafer. Since the wafer is basically not exposed to the air in the steps up to the above drying, it is possible to prevent the generation of the watermark and the regeneration of the natural oxide film. Since the semiconductor wafer is transferred and held substantially in a non-contact manner, it is possible to suppress the generation of particles in the cleaning process.

The semiconductor wafer 400 dried in the drying chamber 340 is held by the first non-contact holding unit 373a of the second transfer robot, and the wafer cassette 3 is held.
It is transported to 80. As described above, the first non-contact holders 363a and 373a are always used for holding and carrying contaminated wafers, but the second non-contact holder 363 is used.
Since b and 373b are used for holding and carrying cleaned wafers, the inside of the cleaning processing system can be isolated from an external contamination source and the wafers can be provided to a subsequent process while maintaining a highly clean state.

The above cleaning processing system is an example,
It goes without saying that various modifications and changes are possible. For example, in the present embodiment, the first and second cleaning processing chambers and the drying chamber are arranged vertically in the processing system, but the present invention is not limited to this, and a third processing chamber may be added. The third processing chamber is, for example, for SC-2 class cleaning, that is, for removing heavy metal contamination of the wafer, and is preferably provided between the second processing chamber and the drying chamber. . Further, although the first processing chamber, the second processing chamber, and the drying chamber are arranged in this order, they may be arranged in another order.

Further, in the present embodiment, the configuration of the non-contact holding unit of the first transfer robot and the second transfer robot is different, but the configuration is not limited to this, and two first transfer robots are arranged. Alternatively, two second transfer robots may be arranged.

Further, in this embodiment, nitrogen gas was used as the inert gas, but the present invention is not limited to this, and helium or the like may be used, or a mixed gas containing a part of the gas such as nitrogen gas or helium. May be. Usable chemicals include acid chemicals other than SC-1, dilute hydrofluoric acid, SC-2, chemicals composed of alkaline and fluoride, and combustible chemicals. However, for flammable chemicals, the present invention is provided in a state where fire resistant and explosion proof structures are maintained.

Further, in the present embodiment, a semiconductor wafer is taken as an example, but the present invention is not limited to this, and it can be applied to a liquid crystal glass substrate and a plasma glass substrate. It can be applied to substrate processing that needs to be prevented.

[0047]

As described above, according to the present invention, a substrate such as a semiconductor wafer is transported in a substantially non-contact state and under an inert gas atmosphere, so that the substrate is shielded from the atmosphere and the like. In addition, it is possible to suppress the generation of particles and the like due to transportation, and it is possible to avoid troubles and troubles caused by the generation of air and particles. further,
By making the processing chamber vertical, it is possible to save space and reduce the size of the system, reduce the amount of inert gas supplied to the housing, and reduce the cost of the entire system. be able to.

[Brief description of drawings]

FIG. 1 is a block diagram showing an outline of a semiconductor wafer cleaning processing system according to an embodiment of the present invention.

FIG. 2 is a diagram showing a wiring layer forming process by a semiconductor wafer cleaning processing system according to an embodiment of the present invention.

FIG. 3 is a plan view of a semiconductor wafer cleaning processing system according to this embodiment.

FIG. 4 is a diagram showing a schematic configuration of a cross section taken along line XX of FIG. 3.

FIG. 5 is a sectional view showing a structure of a wafer cassette.

FIG. 6 is a sectional view showing a configuration of a first cleaning processing chamber.

FIG. 7 is a front view showing a schematic configuration of a first transfer robot.

FIG. 8 is a front view showing a schematic configuration of a non-contact holding unit of the first transfer robot.

9 is a cross-sectional view of the main parts of FIG.

FIG. 10 is a diagram showing a configuration of a second transfer robot, in which FIG. 10 (a) shows a plan view and FIG. 10 (b) shows a front view.

FIG. 11 is a front view showing a schematic configuration of a non-contact holding unit of the second transfer robot.

FIG. 12 is a side view of FIG. 11.

FIG. 13 is a diagram showing a wiring layer deposition process by a conventional cleaning processing system.

[Explanation of symbols]

100, 310: housing, 110: first processing chamber, 120: second processing chamber, 130: a drying unit, 140 and 360: first transfer robot, 150, 370: transfer robot, 160, 380: wafer cassette, 300: cleaning processing system, 320: first cleaning processing chamber, 330: a second cleaning processing chamber, 340: a drying chamber, 400: Semiconductor wafer

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuyoshi Takeda             2-28-18 Shukugawara, Tama-ku, Kawasaki City, Kanagawa Prefecture             Sprout Co., Ltd. F-term (reference) 5F031 CA02 CA05 DA01 FA01 FA02                       FA07 FA11 FA12 GA04 GA10                       GA15 GA28 GA32 GA36 GA44                       GA47 GA49 JA02 JA22 LA15                       MA02 MA23 NA04 NA09

Claims (20)

[Claims] 1. A first and second processing chamber for processing a substrate, and a transfer means for transferring the substrate between the first and second processing chambers, wherein the transfer means does not transfer the substrate. A substrate processing system having a holding means that holds the material in a substantially non-contact state under an active gas atmosphere. 2. The substrate processing system has a housing including at least the first and second processing chambers and the transfer means, and the first and second processing chambers have a vertical structure in the housing. The substrate processing system according to claim 1, wherein the substrate processing system is arranged so that an inert gas is supplied into the housing. 3. The substrate processing system of claim 2, wherein the housing provides a substantially enclosed space and the inert gas is supplied from the top of the housing. 4. The substrate processing system comprises a substrate housing part for housing a plurality of substrates, and a second carrying means for carrying the substrate between the substrate housing part and the first or second processing chamber. The substrate processing system according to claim 1, further comprising: 5. The substrate is a semiconductor wafer, the first and second processing chambers are chambers for cleaning the semiconductor wafer, and each chamber is placed in a substantially inert gas atmosphere. The substrate processing system according to claim 1. 6. The substrate processing system according to claim 1, wherein the inert gas is nitrogen gas. 7. The substrate processing system according to claim 1, wherein the holding unit holds the substrate in a substantially non-contact state by utilizing a Bernoulli effect. 8. The substrate processing system according to claim 5, wherein the holding means places at least one main surface of the semiconductor wafer in an inert gas atmosphere. 9. The substrate processing system according to claim 5, wherein the holding means places opposite surfaces of the semiconductor wafer in an atmosphere of an inert gas. 10. At least a first processing chamber, a second processing chamber, and a drying chamber are vertically arranged in a housing, and between the first processing chamber, the second processing chamber, and the drying chamber. A semiconductor wafer processing system comprising: a first wafer transfer means for transferring a semiconductor wafer, wherein the first wafer transfer means holds the semiconductor wafer in a substantially inert gas atmosphere and in a non-contact state. 11. The semiconductor wafer processing system comprises:
A semiconductor wafer processing system in which the first processing chamber, the second processing chamber, and the drying chamber are arranged in this order from above the housing to below, and an inert gas is supplied from the top of the housing. 12. The semiconductor wafer processing system comprises:
The semiconductor device further includes a wafer storage unit that stores a plurality of semiconductor wafers, and a second wafer transfer unit that transfers the semiconductor wafer between the wafer storage unit and the first processing chamber in an inert gas atmosphere and in a non-contact state. , Semiconductor wafer processing system. 13. The method according to claim 11, wherein the first and second processing chambers have a cleaning spinner for cleaning the semiconductor wafer, and the cleaning spinner has a holding means for holding the semiconductor wafer in a non-contact state. 12. The semiconductor wafer processing system according to item 12. 14. The semiconductor wafer processing system comprises:
And further including a third cleaning processing chamber within the housing,
The semiconductor wafer processing system according to claim 11. 15. The inside of the first, second and third processing chambers can be controlled to an inert gas atmosphere.
4. The semiconductor wafer processing system according to item 4. 16. A substrate processing system having first and second processing chambers and a drying chamber in a housing, wherein an inert gas is supplied to the housing, wherein a cleaning process of a substrate is performed in the first processing chamber. A step of carrying out a substrate treatment from a first chamber to a second chamber by controlling the atmosphere of the substrate substantially in an inert gas atmosphere, a step of cleaning the substrate in the second chamber, the substrate surface And carrying the substrate from the second chamber to the drying chamber by substantially controlling the atmosphere of the inert gas. 17. The substrate processing method according to claim 16, wherein the first and second chambers and the drying chamber are arranged vertically. 18. The substrate processing method according to claim 16, wherein the substrate is a semiconductor wafer, and the inert gas supplied into the housing and the inert gas controlling the atmosphere of the semiconductor wafer are nitrogen gas. 19. The substrate is carried while being held in a substantially non-contact state in the carrying step.
6. The substrate processing method according to 6. 20. The substrate processing method according to claim 19, wherein in the carrying step, the substrate is held in a non-contact state by utilizing Bernoulli effect.